As with most things, you do get what you pay for, but there is a limit where it becomes spending money for the sake of it (for a brand) Had a couple of really cheap ones (less than £10) and I generally found the clips broke if it got too windy as the clips were cheap and flimsy. Also some of them weren't actually waterproof even though they were advertised as being waterproof Though there's no guarantee the more expensive ones will have a better clip or be any more waterproof, but I think if you have the cheapest of the cheap you can't complain its poor quality. Overall there isn't a massive difference and anything is generally better than nothing.